1. Field
The disclosure relates to integrated circuit (IC) design, and more particularly, to the design of IC comparators with built-in hysteresis.
2. Background
In circuit design, a comparator is used to compare the levels of two input voltages, and to generate a logical high or low output signal depending on which input voltage is greater. Comparators find wide application in electronics, e.g., to monitor for when certain voltage levels in a circuit exceed a predetermined reference level.
To improve performance in the presence of noise, some comparators may incorporate amplitude hysteresis. Amplitude hysteresis delays the switching of the comparator output until the difference between the input voltages exceeds a certain minimum threshold voltage. To control the amount of amplitude hysteresis, the minimum threshold voltage may be made adjustable.
It would be desirable to provide simple and robust techniques for designing a comparator incorporating amplitude hysteresis, and to provide such a comparator with adjustable threshold voltages. It would be further desirable to enable such a comparator to accommodate input common-mode voltages over the entire supply voltage range.